The streptavidin-biotin system is being used as a model system to investigatewhether highly ordered surface monolayers can mitigate non-specific cell response to biomaterial surfaces, and whether specific cell responses can be engineered by incorporating appropriate peptide signals into such a surface. At present, ESCA and SIMS are being used to characterize streptavidin adsorbed onto biotin-terminated self-assembled monolayers. Eventually streptavidin derivatives having specific peptide sequences will be employed to study whether cell response can be controlled when these peptide sequences are exposed. Mixed derivative populations will later be investigated. Endothelial cells and smooth muscle cells will be used to determine cell response to the surfaces.